In order to explore the seasonal dynamics and driving factors of zooplankton community structure in a silver carp and bighead carp ecological stocked reservoir, the zooplankton community structure and environmental factors in Sanhe Reservoir were investigated and analyzed in April, July, October, 2023 and January, 2024. A total of 57 species of zooplankton belonging to 16 families were collected, including 45 species of rotifers, 9 species of copepods and 3 species of cladocera. The dominant species of zooplankton in spring, summer and autumn were mainly rotifers, while copepods dominated in winter. There were significant differences in zooplankton abundance and biomass between different seasons, with the highest abundance (245.22 ind./L) and biomass (1.40 mg/L) in spring and extremely low abundance (57.22 ind./L) and biomass (0.37 mg/L) in summer, which were significantly lower than those in other seasons. Non-metric multidimensional scale analysis (NMDS) and community similarity analysis (ANOSIM) revealed that the zooplankton community in Sanhe Reservoir had significant seasonal differences (Global test: R=0.63, P=0.001). Monte Carlo test showed that chlorophyll-a, dissolved oxygen, water temperature and ammonia nitrogen were the main environmental factors affecting the community structure of zooplankton. In addition, the foregut contents of fish and fish stocking and catch data were analyzed. The results showed that the filter feeding pressure of silver carp and bighead carp in the ecological culture reservoir directly drove the changes of zooplankton community structure.